title: Threonine prevents derepression of pyridoxine synthesis in Escherichia coli B.
abstract: After 40 min of pyridoxal starvation, pyridoxine phosphate oxidase-less mutants of Escherichia coli B derepressed pyridoxine biosynthesis 13-fold to a rate of 1.7 X 10(-9) mol/h per mg of cells. Threonine at 100 mg/liter prevented this derepression but did not affect the continued synthesis of pyridoxine. Neither serine nor branched-chain amino acids altered the threonine effect.
mesh_terms: D000597:Amino Acids, Branched-Chain / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011736:Pyridoxine / Q000494:pharmacology*; D012694:Serine / Q000494:pharmacology; D013912:Threonine / Q000494:pharmacology*
chemical_list: D000597:Amino Acids, Branched-Chain; D013912:Threonine; D012694:Serine; D011736:Pyridoxine